Sizzling Garlic Prawns (Gambas al Ajillo) with Chilli and Parsley

Finish. Finely mince 4 garlic cloves and put in big bowl. Smash 4 cloves under this flat side of a knife plus put in a big skillet. Cut into thin pieces leftover four garlic cloves and keep to one side. Add shrimp to bowl with minced garlic. Tip in olive oil (3 tablespoons), kosher salt (3/4 teaspoon), and bicarbonate of soda. Toss to mix well and keep to one side at room temperature. Tip in shrimp shells to skillet using smashed garlic and add leftover olive oil and pepper flakes. Stand over medium-low to low heat and heat, mixing and tossing now and then, till shells are deep ruby red, garlic is pale amber brown, plus oil is intensely aromatic, around 10 minutes. Oil should be lightly bubbling the whole time. Strain through a fine sieve into a little bowl, tossing plus pressing the shrimp shells in order to extract as much oil as possible when ready. Discard shells plus garlic. Return flavored oil to skillet plus heat over a medium-high flame till shimmering. Add sliced garlic and cook, mixing the whole time, till pale golden brown, around 1 minute. Add shrimp and cook, tossing and mixing the whole time till shrimp are barely cooked through, around 2 minutes. Tip in sherry vinegar and parsley and toss to mix. Taste and add salt if it needs it with salt. Eat at once.